Chain-grate furnace.



A. W. BENNIS. CHAIN GRATE FURNAGE.

APPLIGATION FILED JULY 27, 1906.

Patented June 28,1910;

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EVEN??? A. W. BENNIS.

UHAIN GRATE FURNACE.

APPLICATION FILED JULY 27, 1906.

Patented June 28, 1910.

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ALFRED W. BENNIS, OF LITTLE HULTON, ENGLAND.

CHAIN-GRATE FURNACE.

Specification of Letters Patent.

Patented June 28, 1910.

Application filed July 27, 1906. Serial No. 328,054.

To all whom it may concern:

Be it known that I, ALFRED WILLIAM BENNIS, engineer, a subject of theKing of Great Britain, residing in Little Hulton, in the county ofLancaster, in the Kingdom of England, have invented certain new anduseful Improvements in and Connected WVith Chain-Grate Furnaces, ofwhich the following is a specification.

This invention relates to improvements in chain grate furnaces, and hasfor its object to provide a simpler and more eficacious arrangement thanhas hitherto been the case. In chain grates at present constructed, ithas always been found necessary to employ a dumping bar or bridge at theend of the grate, while the feed of the fuel has been regulated by meansof a sliding door, the height of which controls the amount of fuelpassing from the usual hopper to the grate, In order that theimprovements which form the subject matter of the present invention maybe more fully understood, reference will now be had to the accompanyingdrawings, in which,

Figure 1 is a sectional elevation of the furnace; Fig. 2, an end view,with a portion of the grate broken away; Fig. 3 is a plan view of thehinged ash chamber floor and the ash-pit; while Fig. a shows severaldetails of the chain forming the grate; Fig. 5 is an enlarged view ofthe device forming the side air seal.

In these, a is the revolving chain with the links rounded at their endsas in Fig. 4, or otherwise so formed that on the chain passing aroundthe drums at no appreciable gaps are formed between the individual linksand the links do not unduly project the one from the other in thisposition.

Z) is the usual hopper for feeding the fuel to the furnace.

c is a revolving spider mounted on a shaftc and in a casing 0 in whichthe shaft 0 is journaled. This spider is revolved by means of a spurwheel or ratchet e acted upon by any suitable pawl mechanism d which canbe arranged to engage varying numbers of teeth on the ratchet caccording to the number of turns it is desired to give to the spider perminute. The pawl mechanism (Z is operated from any suitablereciprocating rod cl.

f is a depending curved plate hinged at f and counterweighted at 9 soarranged in connection with the spider as to prevent coal other thanthat which enters into the compartments of the spider from passing tothe grate, but capable of swinging away from the spider somewhat toenable any large lumps to pass to the grate.

it represents the doors of the furnace hinged to the furnace front atit. These doors it are provided with spy-holes k normally covered byhinged slides k Toward the back of the grate the usual dumping bar ordumping bridge is dispensed with, and in its place a hinged ash chamberfloor 7' is provided hinged to the masonry of the furnace at j. To theforward end of this ash chamber floor are secured chains 70 which passover suitable pulleys is to winches Z arranged on the front of thefurnace. One of these winches Z is provided with a spur wheel m operatedfrom a hand wheel a through a worm n. This winch Z is connected with thewinch on the other side of the furnace by a shaft 0 and bevel gearing 0,so that both of the winches will be operated together from the one handwheel a. The chains is are removably secured to the ash chamber floor 7'at 70 This ash chamber floor j projects at its outer end somewhat underthe back roller a of the grate, and is provided with a lip n at itsouter end, which in the normal position of the ash chamber floor pressesup or just touches the revolving grate. On the ash chamber floor, and onthe other side of its pivotal point j is arranged a curved plate 29which slides along or contiguous to a fixed plate 9 in the masonry ofthe furnace so as to practically form an air'seal.

Toward the back of the furnace is arranged a channel-iron ash seal 0 towhich is secured a plate 8 carrying a hinged depending lip t which restson the chains of the furnace vertically above the lip c of the ash floorwhen the latter is in its raised position. This arrangement forms a veryeffective air seal and prevents air getting to the back of the furnace.

14 represents the girder or sill-plate on which the brickwork w of thefurnace is built. The girder is provided with a clownwardly projectingrib or lip a.

w represents the framework or casting on which the usual rollers for thegrate are journaled. On this framework on each side is a trough 0 forthe rib to dip into. then this trough is filled with ashes a further andvery effective air seal is formed for the sides of the grate.

F represents the ash-pit and z the rails upon which the grate can bepulled in and out.

The operation of the device is as follows: Fuel is fed in at the hopperb and allowed to pass in regulated quantities past the spider c on tothe grate a. The fuel as it is carried along by the grate a is consumed,and at the end of the grate passes in the form of ashes and clinker onto the hinged ash chamber floor The ash at the same time will bedeposited in the ash seal r and also against the lip 21 of the hingedash chamber floor so as to form air seals for the back of the furnacewhile ash in the troughs 00 form air seals for the sides of the furnace.This prevents admission of air between the sill plates u on whichbrickwork is built and the chain grate frame, minimizing the burningaway of the sill plates through local rapid combustion. lVhen the floorj is sufiiciently loaded with ash and clinker, it is lowered by turningthe hand wheel 72 so as to allow the chains is to wind off the winchesZ. lVhen the ashes have been removed the reverse operation is gonethrough.

If it be desired to increase the feed of fuel to the furnace, the spider0 is speeded up by causing the pawl device (Z to engage more teeth onthe ratchet e on each reciprocation of the rod cl. lVhen it is desiredto withdraw the grate from the furnace the chains is are disconnectedfrom the floor j and secured to any suitable part of the grate, and thelatter pulled out in ordinary manner.

I declare that what I claim is 1. In a furnace, a revolving chain grate;a hinged imperforate ash-chamber floor with its outer end extendingunder the lower straight run of the grate; and means for positivelyholding one edge of said floor up against the under side of said chaingrate; thereby forming an ash air-seal between the floor and the underside of said chain grate.

2. In a furnace, a longitudinal chain grate; a hinged imperforateash-chamber floor, the outer end of which projects under the under sideof the lower straight run of said chain grate; and means for positivelyholding the outer end of said ash-chamber floor against the under sideof said grate, whereby the ashes may collect upon the floor and thusprovide a seal.

3. In a furnace, the combination with a chain grate built up of linksformed with rounded ends; of a hinged ash-chamber floor, the outer endof which in its raised position lies under the under side of the lowerrun of said revolving grate; thereby forming an ash air-seal between theouter end of said ash-chamber floor and said chain grate; a transverseplate between the two runs of said revolving chain grate; and adepending hinged lip on said transverse plate, said hinged lip normallylying on the upper side of the lower run of said chain grate.

4. In a furnace, a chain grate; a hinged ash-chamber floor; a lip on theouter end of said ash-chamber floor; means for bringing said lip upagainst the under side of the lower run of said chain grate; atransverse plate between the two runs of said chain grate; a hingeddepending lip on said transverse plate, the lower edge of which is located on the upper side of the lower run of said chain grate immediatelyabove the lip on the ash-chamber floor; and a transverse ash-sealsecured to the upper part of said transverse plate and located on theunder side of the upper run of said chain grate.

5. In a furnace, a revolving chain grate; a hinged ash-chamber floor; alip on the outer end of said ash-chamber floor normally held against theunder side of the lower run of said chain grate; flexible connectionssecured to said ash-chamber floor; and means for taking in and payingout said flexible connections.

6. In a furnace, a revolving chain grate; a hinged ash-chamber floor;means for forming an ash-seal between the outer end of said ash-chamberfloor and the under side of the lower run of said chain grate; means forraising and lowering said ash-chamber floor; a transverse ash air-seal.for the under side of the upper run of said chain grate; a transverseplate depending therefrom; and a hinged depending lip secured to saidtransverse plate, said hinged lip being located on the upper side of thelower run of said chain grate immediately above the seal formed at theouter end of said ash-chamber floor.

7. In a furnace, a revolving chain grate; a hinged ash-chamber flooradapted when in its raised position to coact with the under run of saidgrate so as to form an air ash seal; masonry forming the ends and sidesof said furnace; an air-seal between said hinged ash-chamber floor andmasonry; troughs on the sides of said chain grate adapted to receive ashfrom the chain grate; and depending lips secured to said masonry at thesides of the furnace, said lips normally lying in the ash which passesinto the troughs.

8. The combination of walls forming a furnace-chamber; a carriagemovable in the furnace-chamber; a chain-grate mounted on the carriage;longitudinal members carried by the carriage and forming troughs at thesides of the grate to receive ash therefrom; signed my name this 12thday of July 1906, depending flanges carried by said Walls and in thepresence of two subscribing Witnesses. entering said troughs; and ahinged ash chamber floor adapted to receive and dis- ALFREDIW" BENNIS' 5charge ashes from the grate and to prevent Witnesses:

the passage of air behind the grate. RICH. CASTLE,

In Witness whereof, I have hereunto ARTHUR W. SMITH.

